Mitigating transmission interference between digital radio and broadband communication devices

ABSTRACT

A broadband device ( 105 ) can detect a proximate narrowband transmission ( 152 ) from a narrowband communication device ( 145 ). The narrowband transmission ( 152 ) can be in close enough proximity ( 155 ) to at least one bearer channel of the broadband device ( 105 ) to result in interference on the narrowband reception ( 152 ) when the broadband device ( 105 ) is transmitting and the narrowband communication device ( 145 ) is concurrently receiving. Responsive to the detecting, the broadband device ( 105 ) can gate a broadband transmission ( 142 ) to ensure the broadband transmission ( 142 ) does not interfere with the proximate narrowband reception ( 152 ). In absence of detecting the narrowband transmission ( 152 ), the broadband transmission ( 142 ) from the broadband device ( 105 ) would not be gated.

FIELD OF THE DISCLOSURE

The present invention relates to wireless communications and, moreparticularly, to mitigating transmission interference between digitalradio and broadband communication devices.

BACKGROUND

The concept of signal interference is well known in the field ofcommunications, and, more specifically, wireless communications. Manysituations exist where signal interference between multiple wirelessdevices degrades the performance of one or more of the devices, based onsignal strengths.

For example, in the home, signals from a microwave, cordless phone, andwireless access point often interfere with each other. Depending on therelative strengths of the signals (i.e., weaker signals introduce lessinterference), the interference results in a slow download, theinability to communicate with a Web server, or a “bad” phone connection(i.e., unable to clearly hear the other party).

In such a situation, the interference is of little consequence, thoughannoying to most users. However, there are situations, such as thosedealing with the wireless communications devices used by public safetypersonnel, where the interference has potentially problematicconsequences, particularly when working in a hazardous environment.

For example, a police officer typically uses a two-way radio forcommunicating with a dispatcher or other officers on the same digitalradio frequency. These digital radio communications may be subject tointerference by other wireless devices (e.g., cell phones, vehicularsubscriber modems, etc.) that operate on nearby frequency bands, whenthe officer is near to these wireless devices. In such a situation, theofficers' time-sensitive communications may become unclear, completelygarbled, or be delayed.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying figures, where like reference numerals refer toidentical or functionally similar elements throughout the separateviews, together with the detailed description below, are incorporated inand form part of the specification, and serve to further illustrateembodiments of concepts that include the claimed invention, and explainvarious principles and advantages of those embodiments.

FIG. 1 illustrates a schematic diagram of a system for mitigating theinterference between signals of broadband user equipment and a digitalradio communications device in accordance with embodiments of theinventive arrangements disclosed herein.

FIG. 2 is a block diagram of a system depicting an interferenceidentification subsystem for use with general digital radiocommunications devices in accordance with embodiments of the inventivearrangements disclosed herein.

FIG. 3 is a schematic diagram of a system illustrating an interferenceidentification subsystem for use with a digital radio communicationsdevice having BLUETOOTH communications components in accordance withembodiments of the inventive arrangements disclosed herein.

FIG. 4 is a frequency band diagram illustrating the interferencepotential between broadband user equipment and digital radiocommunications devices in accordance with embodiments of the inventivearrangements disclosed herein.

FIG. 5 is a state diagram describing the state changes of the broadbanduser equipment when mitigating interference with a digital radiocommunications device in accordance with embodiments of the inventivearrangements disclosed herein.

FIG. 6 is a timing diagram correlating transmissions of the digitalradio and broadband communications devices in accordance withembodiments of the inventive arrangements disclosed herein.

FIG. 7 is a flowchart of a method describing the high-level operation ofthe transmission interference mitigator operating on broadband userequipment in accordance with embodiments of the inventive arrangementsdisclosed herein.

FIG. 8 illustrates two methods describing the detection of a digitalradio communications device within close proximity by an interferenceidentification subsystem in accordance with embodiments of the inventivearrangements disclosed herein.

Skilled artisans will appreciate that elements in the figures areillustrated for simplicity and clarity and have not necessarily beendrawn to scale. For example, the dimensions of some of the elements inthe figures may be exaggerated relative to other elements to help toimprove understanding of embodiments of the present invention.

The apparatus and method components have been represented whereappropriate by conventional symbols in the drawings, showing only thosespecific details that are pertinent to understanding the embodiments ofthe present invention so as not to obscure the disclosure with detailsthat will be readily apparent to those of ordinary skill in the arthaving the benefit of the description herein.

DETAILED DESCRIPTION

Embodiments of the invention address the mitigation of interferencebetween the transmissions of broadband user equipment made in the B13and/or B14 frequency bands and a digital radio communications device,when the digital radio communications device is within a predefinedproximity of the broadband user equipment. A transmission interferencemitigator can be installed upon the broadband user equipment. Thetransmission interference mitigator can be configured to detect theproximity of nearby digital radio communications devices, and gatetransmissions of the broadband user equipment for a predetermined delayinterval, representing an estimated amount of time required by thedigital radio communications device to receive a response to itstransmission.

FIG. 1 illustrates a schematic diagram of a system 100 for mitigatingthe interference between signals 142 and 152 of broadband user equipment105 and a digital radio communications device 145, respectively, inaccordance with embodiments of the inventive arrangements disclosedherein. In system 100, transmissions 142 in the B13 and/or B14 frequencybands of broadband user equipment 105 can interfere with the digitalradio reception 152 of a digital radio communications device 145 whenthe two devices 105 and 145 are proximate to each other, since both theB13 and/or B14 transmission 142 and digital radio reception 152 usefrequencies that are relatively close to each other.

The digital radio communications device 145 can represent an electronicdevice (e.g., two-way radio, land mobile radio, etc.) that uses ahalf-duplex configuration to communicate with other devices over adigital radio network 150. Since the technology regarding the digitalradio communications device 145 and digital radio network 150 are wellknown in the art, only those details of particular import to the presentinvention shall be discussed herein.

In another embodiment, the digital radio network 150 can utilizecomponents of the broadband communications network 140. In yet anotherembodiment, the digital radio network 150 can be communicatively linkedto the broadband communications network 140, such as through anappropriate gateway.

The digital radio communications device 145 and digital radio network150 can represent a system utilized by public safety organizations likethose conforming to the Project 25 standards. For the sake ofillustration, it can be assumed that digital radio reception 152 ofpublic safety personnel are more important than the B13 and/or B14transmissions 142 made by nearby broadband user equipment 105.

The broadband user equipment 105 can represent a variety of computingdevices capable of exchanging B13 and/or B14 transmissions 142 with abroadband communications network 140, including, but not limited to ahand-held computing device, a portable data assistant (PDA), a cellphone, a smart phone, a laptop computer, a mobile data terminal (MDT),and the like. The broadband communications network 140 can represent thehardware and/or software components required to implement acommunications system that supports the use of a wide or broad range offrequencies or bands, such as a long-term evolution (LTE) communicationsnetwork.

Broadband technology (broadband user equipment 105 and broadbandcommunications network 140) is well known in the art, and, as such, onlythose details and functionality utilized by the present invention shallbe discussed herein.

The broadband user equipment 105 can be comprised of various hardware110 and software 120 components. It should be noted that the broadbanduser equipment 105 can include additional hardware 110 and software 120components to support other functionality without affecting thisembodiment of the present invention.

The hardware 110 components can include a processor 112, display 114, atransceiver 116, and a data store 135. The processor 112 can correspondto the electronic circuitry configured to interpret and execute theinstructions of the software 120 components. The display 114 canrepresent a viewing area in which data can be presented to a user of thebroadband user equipment 105.

The transceiver 116 can be the component configured to exchange datawith the broadband communications network 140. The transceiver 116 canutilize the frequency bands associated with B13 and/or B14 transmissions142 to communicate with the broadband communications network 140.

The software 120 components of the broadband user equipment 105 caninclude an operating system 122, a user interface 124, and softwareapplications 126. The operating system 122 can be the computer programconfigured to manage hardware 110 resources and provide a set of commonservices that support operation of the software applications 126. Thesoftware applications 126 can represent a variety of computer programs(e.g., computer-aided dispatch, push-to-talk, video communications,etc.) installed for use upon the broadband user equipment 105.

The user interface 124 can represent a specialized computer programdesigned to provide a basic interaction mechanism for a user. The userinterface 124 can be abstractly thought of as a go-between for a userand the operating system 122 and/or software applications 126. That is,the user interface 124 can be for the broadband user equipment 105 andnot a graphical user interface (GUI) of a specific software application126.

The transmission interference mitigator 130 can represent an additionalcomponent installed within the broadband user equipment 105 to assist inminimizing interference between the B13 and/or B14 transmissions 142 ofthe broadband user equipment 105 when determined to be near a digitalradio communications device 145. The transmission interference mitigator130 can be comprised of hardware and/or software components, dependingupon the specific implementation. When proximate to a digital radiocommunications device 145, the transmission interference mitigator 130can gate the B13 and/or B14 transmissions 142 of the broadband userequipment 105.

It should be noted that gating of the B13 and/or B14 transmissions 142by the transmission interference mitigator 130 can be performed in avariety of manners, such as buffering and/or discarding the dataassociated with B13 and/or B14 transmission 142. Additionally, thetransmission interference mitigator 130 can include multiple methods ofgating and the use of a particular method can be determined onper-application 126 basis.

For example, a time-insensitive application 126 like a Web browser cantolerate a method that delays or buffers the B13 and/or B14transmissions 142 because receiving “old” data is not detrimental to theapplication 126 and/or user. However, a time-sensitive application 126like a push-to-talk (PTT) voice application cannot tolerate delayed B13and/or B14 transmissions 142 because “old” data is often worse than notreceiving the data, which can lead to using a method that discards theB13 and/or B14 transmissions 142 for such applications 126.

Gating of the B13 and/or B14/B14 transmissions 142 can be performed in avariety of ways commensurate with the broadband user equipment 105and/or transmission interference mitigator 130. For example, the bearerdata transmission rate of the broadband user equipment 105 can bereduced by implementing a rate-limiting buffer below the IP stack, suchas in the radio modem device driver software application 126 of thebroadband user equipment 105.

In another embodiment, the bearers of the B13 and/or B14/B14transmissions 142 can be suspended using a 3GPP-defined signalingmethod, such as an extended service request (ESR) message. In the 3GPPstandards (3GPP TS 24301), an ESR message can be used for the purpose ofsuspending data bearers while the broadband user equipment 105 isservicing a circuit-switched voice call.

As applied to the present invention, the ESR message can be used tosuspend the data bearers while the digital radio communications device145 is proximate to the broadband user equipment 105. In thisapplication, the suspension of the data bearers can trigger an“Interface Unavailable” indication to the IP stack or the connectionmanagement middleware of the broadband user equipment 105.

The transmission interference mitigator 130 can be configured to providea visual indication in the user interface 124 that the B13 and/or B14transmissions 142 are currently being gated. The specific visualindication used can be commensurate with the user interface 124 anddisplay 114 of the broadband user equipment 105.

The transmission interference mitigator 130 can include an interferenceidentification subsystem 132 and a data store 135 containing a proximitythreshold 137 and gate interval 138. Data store 135 can correspond to aportion of a data storage device (not shown) of the broadband userequipment 105 allocated for use by the transmission interferencemitigator 130 and/or a non-volatile data storage device integrated intothe transmission interference mitigator 130 and separate to the datastorage device of the broadband user equipment 105, depending upon thespecific implementation of the transmission interference mitigator 130.

The proximity threshold 137 can define a maximum received digital radiosignal power or a minimum distance 155 separating the broadband userequipment 105 and digital radio communications device 145 that requiresthe broadband user equipment 105 to gate B13 and/or B14 transmissions142 in order to reduce interference with digital radio reception 152.The value for the proximity threshold 137 can be hard-coded or can be auser-configurable setting accessed through the user interface 124 or canbe adjusted via well known Over The Air (OTA) device management methods.Configurability of the proximity threshold 137 can allow thetransmission interference mitigator 130 to be fine-tuned on a user orsituational basis (i.e., static vs. transient co-located devices).

For example, Officer A always carries broadband user equipment 105 and adigital radio communications device 145. Therefore, Officer A canspecify a lower proximity threshold 137 since the devices 105 and 145have a small separation distance 155 (static co-location). Officer B,who only carries broadband user equipment 105, can set a higherproximity threshold 137 to account for entering/leaving the broadcastrange of various users of digital radio communications devices 145 whileworking (transient co-location).

It should be noted that the present invention can be incorporated intocommercial band 13 long-term evolution (LTE) devices 105 with a highproximity threshold 137 in order to gate B13 transmissions 142 when apublic safety digital radio communications device 145 is detected withintheir proximity.

The gate interval 138 can define a time period that the transmissioninterference mitigator 130 gates the B13 and/or B14 transmissions 142 ofthe broadband user equipment 105. The gate interval 138 can have adefault setting to represent the average amount of time required for aresponse to a transmission like a value between five and fifteenseconds. Like the proximity threshold 137, the gate interval 138 can beconfigured using the user interface 124 to provide user-customization.

In another contemplated embodiment, the gate interval 138 can bedynamically set by the transmission interference mitigator 130 inaccordance with an adaptive algorithm that monitors the localenvironment. For example, the transmission interference mitigator 130can set a larger gate interval 138 when multiple digital radiocommunications devices 145 are within the proximity threshold 137. Asanother example, the transmission interference mitigator 130 can tracktransmission and response times to identify timing patterns, and predictthe adjustment of the gate interval 138 based upon those timingpatterns.

The interference identification subsystem 132 can be the component ofthe transmission interference mitigator 130 that identifies situationswhere there is the potential for the B13 and/or B14 transmissions 142 ofthe broadband user equipment 105 to interfere with the digital radioreception 152 of the digital radio communications device 145.Implementation of the interference identification subsystem 132 canutilize different means of identifying interference potential, dependingon the components of the digital radio communications device 145, asshown FIGS. 2 and 3.

In another contemplated embodiment, the broadband user equipment 105 caninclude multiple implementations of the interference identificationsubsystem 132, expanding the models of digital radio communicationsdevices 145 that the transmission interference mitigator 130 is capableof handling. In such an embodiment, the transmission interferencemitigator 130 can be configured to utilize the different implementationsof the interference identification subsystem 132 in a preset order(i.e., attempt Method A; if Method A fails, attempt Method B; and soon).

Broadband and digital radio communications networks 140 and 150 caninclude any hardware/software/and firmware necessary to convey dataencoded within carrier waves. Data can be contained within analog ordigital signals and conveyed though data or voice channels. Broadbandand digital radio communications networks 140 and 150 can include localcomponents and data pathways necessary for communications to beexchanged among computing device components and between integrateddevice components and peripheral devices. Broadband and digital radiocommunications networks 140 and 150 can also include network equipment,such as routers, data lines, hubs, and intermediary servers whichtogether form a data network, such as the Internet. Broadband anddigital radio communications networks 140 and 150 can also includecircuit-based communication components and mobile communicationcomponents, such as telephony switches, modems, cellular communicationtowers, and the like.

As used herein, presented data store 135 can be a physical or virtualstorage space configured to store digital information. Data store 135can be physically implemented within any type of hardware including, butnot limited to, a magnetic disk, an optical disk, a semiconductormemory, a digitally encoded plastic memory, a holographic memory, or anyother recording medium. Data store 135 can be a stand-alone storage unitas well as a storage unit formed from a plurality of physical devices.Additionally, information can be stored within data store 135 in avariety of manners. For example, information can be stored within adatabase structure or can be stored within one or more files of a filestorage system, where each file may or may not be indexed forinformation searching purposes. Further, data store 135 can utilize oneor more encryption mechanisms to protect stored information fromunauthorized access.

FIG. 2 is a block diagram of a system depicting an interferenceidentification subsystem 205 for use with general digital radiocommunications devices in accordance with embodiments of the inventivearrangements disclosed herein. System 200 can illustrate a specificembodiment of the interference identification subsystem 132 of FIG. 1.

In system 200, the interference identification subsystem 205 canidentify the potential for interference by determining the separationdistance 155 to a digital radio communications device 145. Thedetermination of the separation distance 155 can be based upon thereceived signal strength of the digital radio transmission 152.

Interference identification subsystem 205 can utilize hardware 210 andsoftware 230 components. The hardware 210 components can include acontrol processor 215 and a radio frequency (RF) power detector 220. Thecontrol processor 215 can represent the electronic component used by theinterference identification subsystem 205 to interpret and execute theinstructions of the software 230 components. The control processor 215can be similar in functionality to the processor 112 of the broadbanduser equipment 105 in FIG. 1.

The control processor 215 can be connected to the processor 112 of thebroadband user equipment 105 by well-known means. This coupling canallow for the control processor 215 to instruct the processor 112 togate the B13 and/or B14 transmissions 142 of the broadband userequipment 105.

The RF power detector 220 can represent the electronic circuitryconfigured to detect the digital radio transmissions 152 (RF signals),such as an RF diode detector or a logarithmic amplifier. The RF powerdetector 220 can include the appropriate signal filtering components soas to focus the RF power detector 220 on the specific frequencies usedby the digital radio communications device 145.

The software 230 components of the interference identification subsystem205 can include a proximity calculator 235 and a proximity event handler240. The proximity calculator 235 can be a computer program configuredto determine the separation distance 155 of the digital radiocommunications device 145 based upon the received signal strengthdetermined by the RF power detector 220.

The proximity event handler 240 can be a computer program configured tocompare the separation distance 155 calculated by the proximitycalculator 235 to the proximity threshold 137 to determine if aproximity event (not shown) is triggered. Triggering of a proximityevent can result in the interference identification subsystem 205indicating to the transmission interference mitigator 130 that its B13and/or B14 transmissions 142 need to be gated.

Since the interference identification subsystem 205 of system 200 basesits detection on the power of the digital radio transmission 152, theinterference identification subsystem 205 can be used with a broad rangeof digital radio communications devices 145. Conversely, by basing itsdetection on the received power of the digital radio transmission 152,the reaction of the interference identification subsystem 205 can bedelayed. That is, after a user of the digital radio communicationsdevice 145 releases the transmit button, a small amount of time canelapse where the interference identification subsystem 205 performs itscalculations to predict proximity and actions for gating B13 and/or B14transmissions 142.

FIG. 3 is a schematic diagram of a system 300 illustrating aninterference identification subsystem 305 for use with a digital radiocommunications device 320 having BLUETOOTH communications components 325in accordance with embodiments of the inventive arrangements disclosedherein. System 300 can illustrate a specific embodiment of theinterference identification subsystem 132 of FIG. 1.

While the prediction method illustrated by system 200 of FIG. 2 isacceptable in most situations, the interference mitigation efficacy canbe improved by system 300. In system 300, the interferenceidentification subsystem 305 of the broadband user equipment 105 canidentify situations of potential interference based on data exchangedwith the digital radio communications device 320 over a personal areanetwork (PAN) connection 335.

The PAN connection 335 can be a BLUETOOTH communications channelestablished between the BLUETOOTH communication components 310 and 325of the interference identification subsystem 305 and digital radiocommunications device 320, respectively. The PAN connection 335 can beautomatically established when the broadband user equipment 105 anddigital radio communications device 320 move within range of each other.

The BLUETOOTH communication components 310 and 325 can represent thehardware and software elements necessary to implement BLUETOOTHcommunications. Typically, BLUETOOTH communication components 310 and325 can include an antenna, BLUETOOTH hardware and firmware (i.e.,BLUETOOTH radio and link controller), a BLUETOOTH software protocolstack, and a BLUETOOTH software application (i.e., the transmissionevent handler 315 and transmission coordinator 330).

The transmission coordinator 330 of the digital radio communicationsdevice 320 can be a BLUETOOTH software application configured to sendthe interference identification subsystem 305 transmission events 340over the PAN connection 335. A transmission event 340 can be anelectronic message containing data about a digital radio transmission152 of the digital radio communications device 320.

For example, a transmission event 340 can indicate that the digitalradio communications device 320 has completed receiving a digital radiotransmission 152. Depending upon the specific implementation of thetransmission coordinator 330 and/or interference identificationsubsystem 305, the transmission event 340 can include additional data,such as user identification, quality of service (QoS) parameters, and apriority of the digital radio transmission 152.

The transmission event handler 315 of the interference identificationsubsystem 305 can perform actions based on the contents of receivedtransmission events 340. When indicated by the transmission event 340,the transmission event handler 315 can trigger the gating of the B13and/or B14 transmissions 142 of the broadband user equipment 105.

Further, the transmission event handler 315 can send the transmissioncoordinator 330 of the digital radio communications device 320 responses(not shown) over the PAN connection 335 in order to synchronize thetransmissions of the broadband user equipment 105 and the digital radiocommunications device 320.

FIG. 4 is a frequency band diagram 400 illustrating the interferencepotential 435 between broadband user equipment and digital radiocommunications devices in accordance with embodiments of the inventivearrangements disclosed herein. Frequency band diagram 400 can beutilized by devices 105 and/or 320 of systems 100 of FIGS. 1 and 3.

Frequency band diagram 400 can visually illustrate the proximity of thefrequency 430 ranges for the frequency bands 405 generally used bydigital radio communications devices and broadband user equipment. Inthis embodiment of the present invention, the frequency bands 405 ofimportance can include Band 13 (B13) 412 and 422 and Band 14 (B14) 414and 424 used by broadband user equipment, and the frequency band 405utilized by P25 digital radio communications devices 416 and 426.

One skilled in the art would recognize that the present invention canapply to other similar situations where narrowband digital radio andbroadband user equipment have been allocated spectrum near each other.When narrowband digital receivers have frequency allocations nearbroadband uplink bands, the present invention can be used to protect thenarrowband receiver from interference from the broadband device.

In this example, both the broadband user equipment and digital radiocommunications device can operate using frequency bands 405 within the700 MHz frequency range, spanning from 746 MHz to 805 MHz. As shown inthe frequency band diagram 400, each frequency band 405 can have adownlink 410 (receiving) frequency 430 range and an uplink 420(transmitting) frequency 430 range.

Since a digital radio communications device utilizes a half-duplexconfiguration (i.e., does not transmit, Tx, when receiving, Rx),transmissions sent on B13 422 and/or B14 424 can occur simultaneous withdigital radio 426 transmissions without causing interference. Thepotential 435 for interference can exist when transmissions sent on B13422 and/or B14 424 occur when the digital radio 416 is receivingtransmissions, as indicated by the arrows.

The Tx/Rx interference potential 435 can be attributed to the closenessof the B13 422 and B14 424 transmit frequency 430 ranges to the digitalradio 416 receiving frequency 430 range. As shown in the frequency banddiagram 400, the minimum frequency 430 for a B13 422 transmission can beonly 2 MHz away from the maximum frequency 430 of digital radio 416reception; a B14 424 transmission can be separated by 13 MHz.

FIG. 5 is a state diagram 500 describing the state changes of thebroadband user equipment when mitigating interference with a digitalradio communications device in accordance with embodiments of theinventive arrangements disclosed herein. State diagram 500 can beutilized within the context of systems 100, 200, and/or 300.

In the state diagram 500, the broadband user equipment can operate in anormal transmit (Tx) state 505 or a gated Tx state 510. Let us assumethat the broadband user equipment begins operation in the normal Txstate 505. The occurrence of event 515 can transition the broadband userequipment from the normal Tx state 505 to the gated Tx state 510.

Event 515 can be expressed in two ways, dependent upon theimplementation of the interference identification subsystem. The RFpower detector can determine that the digital radio device has ended itstransmission, and, is, therefore, potentially receiving a response.Alternately, the broadband user equipment can be informed via theBLUETOOTH connection that the digital radio device is receiving.

Once in the gated Tx state 510, the broadband user equipment can returnto the normal Tx state 505 by event 520 or event 525. Event 520 canrepresent the determination that the digital radio device has beguntransmission or is no longer receiving. Event 525 can correspond to theexpiration of the gate interval or the inability to establish aBLUETOOTH link with the digital radio device.

FIG. 6 is a timing diagram 600 correlating transmissions of the digitalradio 605 and broadband communications 610 devices in accordance withembodiments of the inventive arrangements disclosed herein. The timingdiagram 600 can further illustrate how the state changes of FIG. 5 canrelate to the transmitter states 615 of the digital radio 605 andbroadband (BB) devices 610. Both the radio 605 and BB 610 transmitterscan switch between an ON and an OFF transmitter state 615 (i.e.,transmitting and not transmitting).

In the example shown in timing diagram 600, the radio transmitter 605can start in the OFF state 615 and the BB transmitter 610 can begin inthe ON state 615, which can represent the broadband user equipmentoperating in the normal Tx state 505. As time progresses, the radiotransmitter 605 can switch to the ON state 615, representing messagetransmission and can then return to the OFF state 615 once thetransmission is terminated.

Take for example, an officer calling in an accident over the radio. Theofficer can depress the transmit button of the digital radio device,activating the radio transmitter 605. Activation of the radiotransmitter 605 can be represented by line 640; the radio transmitter605 transitions from OFF to ON 615.

The officer would then speak into the digital radio device whiledepressing the transmit button. Since the transmit button is keptdepressed, the radio transmitter 605 can remain in the ON state 615, asshown by line 642. When the officer is finished speaking, the transmitbutton can be released, causing the radio transmitter 605 to transitionback to the OFF state 615 as represented by line 644.

The completion of a transmission, indicated by the release of thetransmit button that causes the radio transmitter 605 to transition fromthe ON state to the OFF state 615, can be used as the trigger 620 forthe broadband user equipment to begin gating its transmissions. This cancorrespond to event 515 of the state diagram 500 where the broadbanduser equipment transitions from the normal Tx state 505 to the gated Txstate 510.

The gate Tx trigger 620 can represent the event that the interferenceidentification subsystem of the transmission interference mitigator isdesigned to detect. Up until the point in time represented by the gateTx trigger 620, both the radio transmitter 605 and BB transmitter 610can operate proximate to each other without interference 650.

Once the gate Tx trigger 620 is detected by the interferenceidentification subsystem, the transmission interference mitigator cancause the BB transmitter 610 to transition from ON to OFF 615. The BBtransmitter 610 can remain in the OFF state 615 for the duration of thegate interval 635, which can equal the amount of time the digital radiodevice is anticipated 625 to be receiving a response to thetransmission. That is, the BB transmitter 610 can halt transmissionswhen the gate Tx trigger 620 is detected and wait for the gate interval635 to elapse.

Upon expiration of the gate interval 635, event 525 of the state diagram500, the BB transmitter 610 can switch back to the ON state 615 ortransition from the gated Tx state 510 to the normal Tx state 505 untilthe next gate Tx trigger 620 is detected.

As shown in the timing diagram 600, when the BB transmitter 610 resumestransmitting upon expiration of the gate interval 635, there can be anopportunity 630 for the digital radio device to continue receiving itsresponse. For the amount of time corresponding to this opportunity 630,the potential for interference 655 between the BB transmitter 610 andthe digital radio receiver (not shown) can exist.

However, it should be noted that the potential interference 655associated with this opportunity 630 can be minimal, and is, in fact,less than current situations involving proximate digital radio andbroadband devices. Since conventional broadband user equipment lacks thefunctionality of the transmission interference mitigator, the BBtransmitter 610 can remain in the ON state 615 while the digital radiodevice is anticipating receipt 625 of a response. As such, the potentialinterference 655 would, using the current timing diagram 600, begin atline 644 and span the time in which the digital radio device anticipates625 receiving a response and has the opportunity 630 to receiving aresponse.

FIG. 7 is a flowchart of a method 700 describing the high-leveloperation of the transmission interference mitigator operating onbroadband user equipment in accordance with embodiments of the inventivearrangements disclosed herein. Method 700 can be performed within thecontext of systems 100, 200, and/or 300, and/or in conjunction withmethods 800 and/or 820 of FIG. 8.

Method 700 can begin in step 705 where the transmission interferencemitigator can detect a digital radio communications device within itsproximity threshold. The transmissions of the broadband user equipmentcan then be gated by the predefined gate interval in step 710.

Step 705 can be performed in different manners that are commensuratewith the specific embodiment of the interference identificationsubsystem of the transmission interference mitigator.

FIG. 8 illustrates two methods 800 and 820 describing the detection of adigital radio communications device within close proximity by aninterference identification subsystem in accordance with embodiments ofthe inventive arrangements disclosed herein. Methods 800 and 820 candetail the performance of step 705 of method 700 for two contemplatedembodiments of the interference identification subsystem.

Method 800 can correspond to the embodiment of the interferenceidentification subsystem using an RF power detector circuit and canbegin with the receipt of a digital radio signal in step 805. In step810, it can be determined if the strength of the received signal isgreater than the proximity threshold.

When the received signal is stronger than the proximity threshold, step710 of method 700 can be executed. When the received signal is notstronger, the interference identification subsystem can take no furtheraction in step 815. From step 815, flow of method 800 can return to step805 to continue monitoring digital radio signals.

Method 820 can correspond to the embodiment of the interferenceidentification subsystem that utilizes BLUETOOTH communicationscontained in the broadband user equipment and digital radiocommunications device. Method 820 can begin in step 825 where a PANconnection can be established with the digital radio communicationsdevice.

The interference identification subsystem can then receive atransmission event from the digital radio communications device over thePAN connection in step 830. In step 835, the priority of the digitalradio and broadband transmissions can be determined

While it is assumed that digital radio communications should takepriority, step 835 can illustrate how the concepts of the presentinvention can be expanded to include message priorities and/or qualityof service (QoS) requirements. This can be of particular importance whenthe digital radio communications network and the broadbandcommunications network are integrated or share components.

It can be ascertained if the digital radio communication has priority instep 840. When the digital radio communication does not have priority,step 845 can execute where the transmission interference mitigator caninstruct the digital radio communications device to gate itstransmission via the PAN connection.

Step 845 can be modified in accordance with the functionality supportedby the particular digital radio communications device to achieve gatedtransmission. For example, the digital radio communications device canhave the ability to buffer or discard its transmission data during thegate interval.

One skilled in the art would also recognize that the present inventioncan be used to protect narrowband digital radio communications deviceswhen broadband devices have been allocated nearby spectrum for use astime division duplexing (TDD) instead of frequency division duplexing(FDD), as shown in FIG. 2. For TDD communication links, the samefrequency can be used for both downlink and uplink. However, downlinkand uplink communication can be separated in time. Typically, acommunication frame can be defined that contains one or more contiguousregions of uplink and one or more contiguous regions of downlink. Thetiming diagram 500 of FIG. 5 would still apply when broadband links areTDD, but the uplink transmissions would be gated in each TDD broadbandcommunication frame because TDD downlink transmissions do not interfere,and, therefore, would not need to be gated.

Further, one skilled in the art would recognize that the presentinvention can be utilized to protect narrowband digital radiocommunications devices when broadband devices have been allocated forcommunication networks other than LTE, such as WorldwideInteroperability for Microwave Access (WiMAX).

In the foregoing specification, specific embodiments have beendescribed. However, one of ordinary skill in the art appreciates thatvarious modifications and changes can be made without departing from thescope of the invention as set forth in the claims below. Accordingly,the specification and figures are to be regarded in an illustrativerather than a restrictive sense, and all such modifications are intendedto be included within the scope of present teachings.

The benefits, advantages, solutions to problems, and any element(s) thatmay cause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeatures or elements of any or all the claims. The invention is definedsolely by the appended claims including any amendments made during thependency of this application and all equivalents of those claims asissued.

Moreover in this document, relational terms such as first and second,top and bottom, and the like may be used solely to distinguish oneentity or action from another entity or action without necessarilyrequiring or implying any actual such relationship or order between suchentities or actions. The terms “comprises,” “comprising,” “has”,“having,” “includes”, “including,” “contains”, “containing” or any othervariation thereof, are intended to cover a non-exclusive inclusion, suchthat a process, method, article, or apparatus that comprises, has,includes, contains a list of elements does not include only thoseelements but may include other elements not expressly listed or inherentto such process, method, article, or apparatus. An element proceeded by“comprises . . . a”, “has . . . a”, “includes . . . a”, “contains . . .a” does not, without more constraints, preclude the existence ofadditional identical elements in the process, method, article, orapparatus that comprises, has, includes, contains the element. The terms“a” and “an” are defined as one or more unless explicitly statedotherwise herein. The terms “substantially”, “essentially”,“approximately”, “about” or any other version thereof, are defined asbeing close to as understood by one of ordinary skill in the art, and inone non-limiting embodiment the term is defined to be within 10%, inanother embodiment within 5%, in another embodiment within 1% and inanother embodiment within 0.5%. The term “coupled” as used herein isdefined as connected, although not necessarily directly and notnecessarily mechanically. A device or structure that is “configured” ina certain way is configured in at least that way, but may also beconfigured in ways that are not listed.

It will be appreciated that some embodiments may be comprised of one ormore generic or specialized processors (or “processing devices”) such asmicroprocessors, digital signal processors, customized processors andfield programmable gate arrays (FPGAs) and unique stored programinstructions (including both software and firmware) that control the oneor more processors to implement, in conjunction with certainnon-processor circuits, some, most, or all of the functions of themethod and/or apparatus described herein. Alternatively, some or allfunctions could be implemented by a state machine that has no storedprogram instructions, or in one or more application specific integratedcircuits (ASICs), in which each function or some combinations of certainof the functions are implemented as custom logic. Of course, acombination of the two approaches could be used.

Moreover, an embodiment can be implemented as a computer-readablestorage medium having computer readable code stored thereon forprogramming a computer (e.g., comprising a processor) to perform amethod as described and claimed herein. Examples of suchcomputer-readable storage mediums include, but are not limited to, ahard disk, a CD-ROM, an optical storage device, a magnetic storagedevice, a ROM (Read Only Memory), a PROM (Programmable Read OnlyMemory), an EPROM (Erasable Programmable Read Only Memory), an EEPROM(Electrically Erasable Programmable Read Only Memory) and a Flashmemory. Further, it is expected that one of ordinary skill,notwithstanding possibly significant effort and many design choicesmotivated by, for example, available time, current technology, andeconomic considerations, when guided by the concepts and principlesdisclosed herein will be readily capable of generating such softwareinstructions and programs and ICs with minimal experimentation.

The Abstract of the Disclosure is provided to allow the reader toquickly ascertain the nature of the technical disclosure. It issubmitted with the understanding that it will not be used to interpretor limit the scope or meaning of the claims. In addition, in theforegoing Detailed Description, it can be seen that various features aregrouped together in various embodiments for the purpose of streamliningthe disclosure. This method of disclosure is not to be interpreted asreflecting an intention that the claimed embodiments require morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive subject matter lies in less than allfeatures of a single disclosed embodiment. Thus, the following claimsare hereby incorporated into the Detailed Description, with each claimstanding on its own as a separately claimed subject matter.

We claim:
 1. A method for mitigating radio frequency interferencecomprising: detecting at a broadband device, a proximate narrowbandtransmission from a narrowband communication device, wherein thenarrowband transmission is in close enough proximity to at least onebearer channel of the broadband device to result in interference on thenarrowband reception when the broadband device is transmitting and thenarrowband communication device is receiving concurrently; andresponsive to the detecting, the broadband device gating a broadbandtransmission to ensure the broadband transmission does not interferewith the proximate narrowband reception, wherein in absence of detectingthe narrowband transmission the broadband transmission from thebroadband device would not be gated.
 2. The method of claim 1, whereinthe broadband transmission and the narrowband reception operate in a 700MHz frequency band.
 3. The method of claim 1, wherein the gating of thebroadband transmission is for a previously established time between fiveand fifteen seconds.
 4. The method of claim 1, wherein the previouslyestablished time is a user-configurable time, which is configurable atthe broadband device.
 5. The method of claim 1, wherein the broadbanddevice is a 3GPP-conforming network communication device thatcommunicates with a mobile broadband network, wherein the narrowbanddevice is a two-way radio that communicates with a base station andother two-way radios.
 6. The method of claim 1, further comprising: thebroadband device utilizing a radio frequency (RF) power detector todetect narrowband transmissions from the narrowband communicationdevice, wherein the gated transmission of the broadband device isenacted for a previously configured delay between five and fifteenseconds upon the detection of the proximate narrowband transmission. 7.The method of claim 1, further comprising: the broadband deviceutilizing a wireless personal area network (PAN) transceiver to detectreception indication data conveyed by the narrowband communicationdevice over a personal area network, wherein the broadband device usesthe reception indication data to gate the broadband transmission whileany proximate narrowband reception from the narrowband communicationdevice is occurring.
 8. The method of claim 1, further comprising:detecting a transmission from the narrowband device using a radiofrequency (RF) power detector component of the broadband device; at thetime of the detection of the transmission termination, determining thatthe broadband device is transmitting data that is likely to causeinterference after the detected transmission termination; haltingtransmission of the data being transmitted from the broadband device;waiting for a delay period of a previously determined time between fiveand fifteen seconds; and after the delay period, automatically enablingtransmission of data from the broadband device.
 9. The method of claim1, further comprising: establishing a personal area network (PAN)connection between PAN components of the broadband device and thenarrowband communication device; conveying data over the PAN connectionfrom the narrowband communication device to the broadband device toindicate when receptions from the narrowband communication device areoccurring; at the time that receptions are occurring from the narrowbanddevice, as determined from the data conveyed over the PAN connection,determining that the broadband device is to transmit data that is likelyto cause interference with the detected reception; halting transmissionof the data from the broadband device for periods where the narrowbandcommunication device is receiving, as determined from the data conveyedover the PAN connection; and automatically enabling transmission of datafrom the broadband device when the narrowband communication device is nolonger receiving, as determined from the data conveyed over the PANconnection.
 10. The method of claim 1, further comprising: responsive togating, determining whether gated transmissions are to be buffered forlater transmission or discarded; wherein the method of determiningwhether gated transmissions are to be buffered for later transmission ordiscarded utilizes one or combination of: data traffic type, quality ofservice, duration of gating period; and if results of the determiningindicate gated transmissions are to be buffered, the broadband devicebuffering the gated transmission for a duration after which the gatedtransmissions are transmitted by the broadband device; and if results ofthe determining indicate gated transmissions are to be discarded, thebroadband device discarding the gated transmissions.
 11. The method ofclaim 1, wherein the gating further comprises one or combination of:implementing a rate-limiting buffer below the IP stack to gate thebroadband transmission; and utilizing a 3GPP-defined signaling method tosuspend the broadband transmission.
 12. A computer program product formitigating radio frequency interference between two proximatecommunication devices, the computer program product comprising: one ormore computer-readable, tangible storage devices; program instructions,stored on at least one of the one or more storage devices, to detect ata broadband device, a proximate narrowband transmission from anarrowband communication device, wherein the narrowband transmission isin close enough proximity to at least one bearer channel of thebroadband device to result in interference on the narrowband receptionwhen the broadband device is transmitting and the narrowbandcommunication device is receiving concurrently; and programinstructions, stored on at least one of the one or more storage devices,to, responsive to detecting the proximate narrowband transmission, gatea broadband transmission to ensure the broadband transmission does notinterfere with the proximate narrowband reception, wherein in absence ofdetecting the narrowband transmission the broadband transmission fromthe broadband device would not be gated.
 13. A system for mitigating RFinterference between narrowband public safety and broadbandcommunications devices comprising: a narrowband radio communicationsdevice configured to transmit and receive narrowband communications; anda 3GPP-conforming network communications device configured tocommunicate with a 3GPP-conforming network, said 3GPP-conforming networkcommunications device further comprises: a transmission interferencemitigator configured to mitigate the potential for interference betweenthe narrowband radio communications device and the 3GPP-conformingnetwork communications device by selectively throttling transmissions ofthe 3GPP-conforming network communications device when receptions of thenarrowband radio are likely to be occurring within close proximity tothe 3GPP-conforming network communication device.
 14. The system ofclaim 13, wherein the narrowband communications are in close enoughproximity to at least one bearer channel of the 3GPP-conforming networkcommunications device to result in interference on the narrowbandcommunications when the two devices are concurrently transmitting andreceiving.
 15. The system of claim 13, wherein the narrowbandcommunications are in the 700 MHz frequency band and wherein at leastone bearer channel of the 3GPP-conforming network device operates in the700 MHz frequency band.
 16. The system of claim 13, wherein said3GPP-conforming network communications device further comprises: a radiofrequency (RF) power detector configured to detect narrowbandtransmissions from the narrowband radio communications device; a gateinterval defining a quantity of time that transmissions of the3GPP-conforming network communications device are to be selectivelygated, wherein the transmission interference mitigator is configured togate transmissions for the quantity of time responsive to the radiofrequency power detector detecting termination of the narrowbandtransmissions, wherein the quantity of time is between five and fifteenseconds, which represents a time delay expected for a person to respondto a two-way radio voice communication prompt.
 17. The system of claim16, wherein the radio frequency power detector is configured to detectwhen narrowband transmissions from the narrowband radio communicationsdevice stops, wherein the transmission interference mitigator isconfigured to gate otherwise unabated transmissions from the3GPP-conforming network communications device responsive to detectingthat narrowband radio communications has stopped its transmissions. 18.The system of claim 13, wherein the narrowband radio communicationsdevice further comprises: a personal area network transceiver configuredto convey data over a wireless personal area network to indicate withindata when receptions of the narrowband device start and stop, whereinthe 3GPP-conforming network communications device comprises a personalarea network transceiver configured to receive data over the wirelesspersonal area network and to coordinate transmissions of the3GPP-conforming network communications device to occur when noreceptions are occurring from a narrowband radio communications devicewithin personal area network range of the 3GPP-conforming networkcommunications device.
 19. The system of claim 18, wherein saidtransmission interference mitigator establishes a priority level fortransmissions from the 3GPP-conforming network communications device anda priority level for receptions from the narrowband radio communicationsdevice, wherein data conveyed over the personal area network ensuresthat whichever of the 3GPP-conforming network device and the narrowbandradio communication device having the lowest priority will gatetransmissions while receptions by the other one of the devices isoccurring wherein the personal area network transceiver of thenarrowband radio communications device and of the 3GPP-conformingnetwork communications device are each BLUETOOTH transceivers.
 20. Thesystem of claim 18, wherein the personal area network transceiver of thenarrowband radio communications device transmits messages over thepersonal area network when narrowband receptions of the narrowbandcommunications device start and end, wherein the transmissioninterference mitigator uses knowledge of when the narrowbandcommunications devices starts and ends its receptions to ensure that notransmissions from the 3GPP-conforming network communications device areoccurring concurrent with receptions of the narrowband communicationsdevice.